Antimutagenic activity and inhibition of melanoma cells by soymilk fermented with Lactobacillus plantarum TWK10 and Pediococcus pentosaceus MK6

• Main Authors: Yi-Ming Chen, 陳奕鳴
• Other Authors: Tsung-Yu Tsai
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/09091476428396043607

碩士 === 輔仁大學 === 食品科學系 === 97 === Plant origin lactic acid bacteria (POLAB) is isolated from plants and more tolerance to acids and bile salts than animal origins. Soymilk contains rich in high-quality proteins and isoflavones which are found several biological activities, such as anti-tumor, and improvement the menopausal syndromes and the risk of and atherosclerosis. Melanocytes reside at basal layer of epidermis and hair follicle. In general, ultraviolet radiation (UV) acts directly to proliferation of melanocytes. This research, was divided into third parts. In first parts, high β-glucosidase strains POLAB were isolated from fermented vegetables. The second parts, the soymilk fermented by selected strains were evaluated the isoflavone contents, antioxidant activity and antimutagenicity. The third parts, B16 mouse melanoma cells (B16-F0) were co-cultured with fermented soymilk, and investigated the inhibition of cell viability and melanogenesis. As the results, the β-glucosidase producing strains, Lactobacillus plantarum TWK10 and Pediococcus pentosaceus MK6, were identified by API 50 CHL identification system and multiplex polymerase chain reaction, and the highest activities of β-glucosidase, 10.95±0.38 and 9.00±1.30 mU/Log CFU were determined at 12 h cultivation. Aglycone isoflavones (daidzein and genistein) were investigated by high performance liquid chromatography. In L. plantarum TWK10-fermented soymilk, the contents of daidzein (143.51±0.69 μg/mL) and genistein (113.08±0.61 μg/mL), was relatively higher than other fermented soymilk at 48 h cultivation. In anti-oxidative assays, reducing activity, scavenging of α,α-diphenyl-β-pricrylhydrazyl (DPPH) radicals and chelation of ferrous ion were evaluated and the antioxidative activity in fermented soymilk with L. plantarum TWK10 was significantly higher than other fermented and non-fermented soymilk (p<0.05). As the results of antimutagenic activity on Salmonella Typhimurium TA100, fermented soymilk ethanol extract (5mg/plate) fermented with P. pentosaceus MK6, L. plantarum TWK10 showed antimutagenic activity of 70.82%, 72.66% against sodium azide and 87.66%, 87.01% against 2-aminofluorene which were higher than non-fermented soymilk 44.52%, 78.08% against sodium azide and 2-aminofluorene,respectively. In 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, the inhibitions of B16 melanoma cells were determined, and the P. pentosaceus MK6 and L. plantarum TWK10 fermented soymilk inhibited the viabilities of melanoma cells, 39.73%, 42.36%, respectively. The melanin in B16 melanoma cells decreased to 66.30% and 63.17% by fermented soymilk (100μg/mL) with P. pentosaceus MK6 and L. plantarum TWK10. The ethanol extract of fermented soymilk (100 μg/mL) by P. pentosaceus MK6 and L. plantarum TWK10 exhibited the inhibition of tyrosinase activity, 26.27% and 37.76%, respectively. The expression of tyrosinase protein level in melanoma cells were decreased to 55.43% and 49.41% by P. pentosaceus MK6 and L. plantarum TWK10 fermented soymilk (100 μg/mL) which were higher than non-fermented soymilk of 86.59%. In conclusion, the fermented processes improve the biological and antioxidant activity to inhibit of B16 mouse melanoma cells viability, melanin contents and intracellular tyrosinase. This fermented soymilk is a potential product which will be developed as functional foods.